Jealousy (Look What You've Done to Me)
by Drowned-dreamer
Summary: Emma's been fighting the darkness from taking over, but will a misunderstood moment between Killian and Lilly push her over the edge? Jealous!DarkSwan


**Jealousy (Look What You've Done to Me)**

 **SUMMARY: Emma's been fighting the darkness from taking over, but will a misunderstood moment between Killian and Lilly push her over the edge? Jealous!DarkSwan**

 **PAIRING: Captain Swan**

 **WARNING: Heavy angst, violence**

 **DISCLAIMER: I do not own OUAT or its characters.**

 **A/N- This was an idea I'd been toying with for some time, but the spoiler pictures of Dark Swan and Killian together really just cemented it. Fair warning, apparently angst is my favorite thing to write, and there certainly is a lot of it here. As always, please REVIEW! And thank you for reading.**

* * *

It started out as a simple gesture. A smile. A laugh. Because the sheer relief he felt had to come out some way. He should have known better.

Killian had first noticed Lilly browsing through the racks of books located in the far wing of the library when he was doing research on Merlin. At the time, he was so focused on finding Emma and bringing her home, he barely registered the girl's presence. A quick nod of appreciation- that was all- when she pointed out a book on Camelot he was searching for had been the only interaction they shared.

"You're Emma's boyfriend?" She asked him the next time they ran into each other in the same section of the library. She didn't even wait for a response before she quickly darted her gaze back to the section on dragons she was scouring.

Killian flinched, the word cutting him deeper than he had anticipated, but replied with a gruff, "Aye."

"I'm really sorry about what happened," she said quietly, then pulled out a book and walked away.

Days wore on, with Emma no closer to being found. All they had learned was that the dagger didn't work anymore, but no one was sure whether it was because the rules had changed or whether it was because Emma was simply no longer in their realm.

Killian went back to the library. He saw Lilly there more frequently, still pouring over anything and everything about dragons that she could find. The only reason Killian ever knew that was because apparently all the books on King Arthur and Camelot and Merlin were housed in the same location. Despite the proximity, their interactions with each other were even less than before. A brief nod; a hesitant "Hello."

As it turned out, the research wasn't necessary. As with so many things in Storybrooke, finding Emma in Camelot had been nothing short of a miraculous (and suspiciously timed) coincidence brought about by a vengeful Zelena. Turned out, the magical cyclone she was trying to summon made great transportation to other realms, provided you had adequate shelter, that was.

By the time the dust had settled around Granny's restaurant, Killian knew his luck had changed. It was like he could feel her presence there from the moment he arrived. Like someone had filled the room with sweet flowers and a soft breeze. So when they found Emma, (who had been there, in Camelot, all this time), he knew she was still his Emma. He thought everything was going to be okay.

Sure, there were times she struggled against the impulses of the Dark One, but mostly she was still light and still good and still…Emma, so he never worried that she would succumb. After all, she was still the Savior, too.

They should have never gone back to Storybrooke.

Seeing all the familiar places and people should have helped her, should have reminded her what she was staying good for. It didn't. As life continued, all those reminders did was push her farther into the darkness. Not that anyone noticed. Emma was always good at hiding.

Of course, Killian noticed. How could he not? He saw the way her lips would twitch into a sneer when one of the dwarves came barreling down the street. Felt the way her body would go rigid and cold when her parents came on a little too strong. Hated the way her fingers stretched and curled when she watched Henry with Regina and Robin. Those were the moments he lost hope and let his own fears come to light. What would happen if he was wrong? What if someday, the darkness became too much and she slipped.

With the shadow of his dread hanging over him, he returned to the library. It was more imperative than ever that he locate the Sorcerer, not that he had ever really stopped looking. When they had travelled to Camelot, they had learned much about Merlin's history, but not where they could find him. It seemed that no one had seen him in many years.

Back to library it was, then.

Lilly, of course, was still at the there. She had her dragon books spread out on a table, thoroughly engrossed in whatever she was reading. Killian gave her a brief "Morning, lass," so as not to startle her and began to walk towards the shelves.

"Hey, Killian?" Lilly said suddenly. It was the first time she'd even acknowledged that she knew his name, let alone used it.

He turned around and looked her. She was nervous for some reason, fiddling with her wrist and her long chestnut hair. "Aye? Something I can help you with?" He asked.

Turning her eyes towards him, she seemed to come to some sort of decision and she took a deep breath. "I know you've been looking for information on Merlin for Emma. I've found a book you might not have seen. It was miss-shelved," she added as an afterthought, tucking her hair behind her ears and trying hard not to look at him. "I don't know. I thought maybe it could help."

Killian was shocked to say the least. He quickly crossed the space and sat down in a chair at the table beside her. "What have you found?" He asked unceremoniously. His mind raced with questions while he watched her intently for any lies. Why was she be helping him? Weren't her and Emma rivals? What would she want in return?

Under his scrutiny, she swallowed hard and began riffling through the pile of books until she came upon a small yellowed journal of sorts. She held it out to him without commentary.

With a nod, he took it from her and began to peruse its pages. Most of it was hand-written and extremely difficult to decipher, but she was right, it was clearly about Merlin. He placed his hook on top of the table and furrowed his brow at her. "No offense, lass, but why the interest? Why are you helping me?"

Lilly looked conflicted, her dark eyes searching for words to explain what she was doing. "I wanted a chance," she said so quietly that he was forced to lean closer to hear her. If she noticed his proximity, she wasn't concerned by it, too focused on her own thoughts. "Every choice I've made has only caused people harm. I'm tired of it. I thought being here might, I don't know, reset the balance. So far, it's been working, I guess." She sighed, her fingers coming up to nervously twist her long locks into a curl.

"I hurt Emma once," she says after a slight pause. "I didn't really mean too. But I did, although that's not how I saw it at the time. I blamed her for everything for years, but I know now that it wasn't really her fault. She had no more choice in the matter than I did. And now…what she did…I can't even imagine what it's like to have to give everything up you love and purposefully curse yourself. I didn't know how else to help, but when I saw that," she gestured towards the book in his hand, this time actually looking up and meeting his eyes. "I guess I thought it couldn't hurt."

Killian blinked, not knowing what to say. Swan had told him about some of her past with her friend, but there was still much he didn't know. However, when he looked at her, she seemed sincere. Regardless of her motivations, though, he was grateful for the help. "Thank you, lass."

There was a strangely comfortable silence that fell around them, and Killian merely shot off a quick grin at her and went back to reading. Lilly, too, resumed her research and for a short while, neither one spoke. Suddenly, Killian shouted and began to laugh. He leaned over towards Lilly with a wide grin, intending to show her what he'd found, and said, "I think this might be what—"

Whatever he was going to say was lost in a horrible rush of wind and confusion as Killian was violently jerked back and flung against a far wall. He fell with a pained grunt, shaking his head in confusion. As his vision cleared, he looked up, expecting to see the Crocodile or some other villain of his long acquaintance, but found his Swan instead.

Only, she no longer looked like his Swan. Gone was her light. Dark swirls of magic were surrounding her as she stalked into the room. The new style of severely pulled back hair and sharp black clothing now seemed to fit her. This wasn't Emma. This was the Dark One. Even though her back was turned to him, he could sense the shift in the air that marked its presence. Still dazed from his fall, though, all he could do was watch as she stalked across the little nook, books and papers scattering in her wake, as she raised her hand and held it stiffly aloft.

On the other side of the room, Lilly was pinned to the wall, her hands scrambling with an invisible force at her throat that was choking the life from her. An invisible force clearly caused by his Swan.

"Thought you could take whatever you please, Lilly?" Swan asked the girl, her voice sounding strangely child-like and small.

"Emma?" He rasped, hastily pushing himself up off the ground and running to her. Before he could reach her though, she tilted her head back to look at him, and for the first time, Killian saw not his Emma, but the cold, calculating stare of the Dark One. It stopped him mid-stride. His heart shattered as his hope, his future, his love looked at him with no warmth in her eyes.

 _no no no not her please not like this_

She smiled wickedly at him, as her green eyes were swallowed up by a sea of black. Even her golden hair now shimmered with silver, like trading night for day. "What the bloody hell are you doing, Swan?" He asked, unsure how he managed to even find his voice.

It was clear what she was doing. She was trying to kill Lilly but strangling her with her magic. The poor girl was turning red and her breath was starting to sound wheezy and faint. What wasn't clear was why.

"I'm protecting what's mine," she replied, her voice like steel. "She needs to be taught a lesson."

"What are you talking about?" He took a step closer, aching to reach out and pull her back into the light, to pull her away from this darkness. "Let her go, love. She's done nothing to you."

Emma spun so fast on him, he stumbled back on a fallen book. Thankfully, it was enough of a distraction to release Lilly from her choke hold and he saw her fall to the ground in a semi-conscious heap. _"She's done nothing?"_ Emma repeated, practically hissing out the words. "You're telling me that she wasn't flirting with you, wasn't trying to seduce you and take you away from me? Because that's what she does, Hook. She _takes_."

Trying not to flinch from the tone in which she used his old moniker, he knew he had to distract her long enough for Lilly to flee. The girl in question was slowly coming stirring, but wasn't quite in a state to run.

"I assure you," he said, speaking in a low, even tone so as to keep her attention and not upset her "that whatever you think happened did not." It was like he had slapped her across the face. Calling her out on her misplaced jealousy had obviously been the wrong way to go.

She looked at Killian again, her eyes hardening into sharp points. "Then again, maybe you're right. Maybe she didn't do anything after all. Maybe it was _you_."

How could she think that of him? After everything he had done to prove himself to her, would it ever be enough? He shook himself out of this train of thought, reminding himself that this wasn't his Emma. It was the Dark One, and that darkness inside her fed on her deepest fears in order to destroy the love they had between them. It whispered lies about his unfaithfulness, took every opportunity to shatter their trust. He knew how the darkness worked, and he knew he couldn't let it do that to her. "Emma. Please. This isn't you."

"Oh, and I'm supposed to believe you, _Hook_?" She said his name like a curse, the dark tendrils of magic floating along besides her shooting upward with her rage. Without realizing it, he had taken several steps backward until he could feel the wall behind him. He hadn't wanted to show weakness in front of her, but neither could he lash out. No matter was, his Emma was still there.

Instead, he forced himself to face her, to look into the eyes of the Dark One unflinchingly, trying to break through to draw out the real Emma buried beneath the monster. Maybe he couldn't see her yet, but he knew she was there. "Yes, my love. Because you know me. You know my love for you. I would never betray your trust."

"Lies!" She screeched, the magic lashing at him like a whip, leaving burning scars along his skin as it made contact. His teeth clamped together in pain, but he wouldn't let her see his fear. "All lies. You're a man. Why should I believe you?"

Killian reached up, cupping her chin with his good hand. She didn't move away and he sighed in relief. "Emma, look at me. You know I'm not lying to you. I love you, my darling."

For an all-too-brief moment, he saw the darkness falter, saw her soften under his touch. Hope burned brightly in his chest, and he offered her the sweetest smile he could. Her eyes started to lose some of their black cast and it seemed like she wanted to smile back. Her eyes flickered to his lips like she always did right before she kissed him. She leaned in, and he hardly dared breathe.

 _That's it, love. Come back to me. Come back._

Then it all went wrong. She seemed to inwardly retract, roughly shoving aside his hand as her resolve hardened. "You will betray me, just like everyone else has. You will leave," she stated with surety. Her eyes left his lips and dropped briefly to his chest. Then her head shot back up, her face aglow with a devious light. "Here, let me prove it to you," she cooed, and before he could figure out her words, she shoved her hand inside his chest.

He didn't cry out, even though the pain was unbearable. He was too shocked for that. He watched her remove her hand, and with it, his heart. The bright red pulse made her pale skin glow pink in its light. She held it carefully, looking at it with wonder, like a child looks at a new toy, even stroking it gently with the tips of her fingers. "See?" She said, the black of her eyes was laced with red as she looked up to meet his gaze. "You told me you were a survivor. You told me…" She stopped herself, cutting off whatever train of thought she had been about to go down, like it was painful. Instead, she flexed her fingers over his heart, curling them just the slightest bit tighter. It didn't hurt him, exactly, but he felt the pressure. "But all I have to do is squeeze and prove myself right."

The magic surrounding her picked up, the wisps of dark magic entwining him, tying him tightly to her like ropes. For a moment, a lunatic thought crossed his mind about how everyone always tied him up (and not in the good way), before he came back to his senses.

He knew he should speak out, to decry the evil inside her, but with his heart in her hands, all he felt was resigned. Unlike the last time she had held it, he could see her intention was not to just look at it and put it back. No, this time, she wanted to watch it burn.

He would die at her hand and there was nothing he could do to stop it. How do you save yourself from the Savior?

"Emma! Stop!" An unexpected voice cried out. Emma tilted her head around, and Killian followed, surprised to see Lilly standing just behind her. Lilly's face was a mix of horror and confusion. The thought crossed his mind that she had probably never seen a heart taken before, and he felt bad that she was going to have to experience it the hard way. (Not that there was any easy way)

His thoughts tended towards the abstract when he no longer had a heart in his chest. Perhaps he needed to focus harder.

"Come to save your lover?" Emma sneered. "Well, it's too late. But don't worry. Once he's dead, I'll make sure you join him." She tossed a smirk in Lilly's direction, and continued to stare at his heart. And then it dawned on him. For whatever reason, she was holding herself back. It was enough to give him hope that his Emma was still there and that she would come to her senses before she did something she would regret the rest of her life.

Lilly, apparently, was made of sterner stuff than he had realized and she was not to be daunted by Emma's threats. "You don't want to do this," she cried, her eyes frantically watching to make sure Emma wasn't going to squeeze his heart tighter just to spite her. "Nothing happened here. This was all just a mistake. He was happy because he had found out how to find Merlin. That's it. He was just trying to help you. He loves you. Look at him," she begged, and Killian wondered again why she cared about what happened to him. "Look at what you are doing to the man you love."

For some reason, Emma seemed to listen. She looked up, meeting his eyes and he could tell that she was letting herself truly see exactly what she was doing to him. But whatever she was looking for in him, it wasn't enough to overcome the darkness. "How can I love a man who lies?" She said softly, almost sadly.

"He didn't lie," Lilly countered, her voice rising in frustration.

Emma shrugged. It was like the truth no longer mattered to her. She had that hard set to her jaw that said her mind was made up and there was no convincing her otherwise. Killian had come up against that wall far too many times to know just how hard it was to scale. "When I kill him, he'll be a liar. He promised me he was a survivor. He told me I wouldn't lose him."

Lilly looked at her like she was joking, rolling her eyes at her twisted logic. "You're only going to lose him if you kill him, not prove him wrong. This isn't some sort of game. I know you don't want him dead. A part of you has to know that you still love him."

"How can he love this?" She whispered, and then it all clicked into place for him. Killian could see the real reason why she had fallen, the real reason behind the slide into darkness. It was because of her darkest fear. Her biggest secret. The one that kept her feeling like a lost girl. The one that told her she would never be good enough. He should have known all along. After all, they shared the same fear.

"I'm the Dark One now, and he's spent his life trying to destroy it. He _can't_ love me."

He could no longer let this go on. Even if she still killed him, she had to know how he felt. "Emma, it doesn't matter. I love you, darkness and all."

"No!" She yelled, shaking her head, refusing to listen. He could see the darkness and light warring with each other inside her. He braced all of his hope on her light winning out. And for a moment, it seemed like it was.

Then, something happened and the everything fell apart. It was like a part of the Dark One that had only been lying dormant all this time was unleashed within her. Her light was going, dimming like a dying candle in a sea of night. As he watched helplessly, her soft, pale skin began to a shimmer like it was covered by diamonds. She was slipping away from him with a smile on her face. The claws of her hand crushed together harder. This time he couldn't help the groans of pain as he fell to his knees in front of her.

"Emma! No!" Lilly screamed, trying to get the heart from her hand. Emma easily deflected her with her magic, waving her unoccupied hand and flinging her back across the room without even looking. Lilly fell hard against a shelf with a sickening crack, books tumbling all around her.

He looked up, determined to meet death in the eye. What a fool he had been! How had he not known what the Dark One had been doing to her? From the moment she had taken that dagger, it had slowly been playing on all her fears, shoring itself up within her sky high walls. It had made itself right at home and no one had been the wiser, not even Emma. He could see the desire now, in the inky depths of her gaze. She wanted the darkness. She had made friends with it. It was keeping the pain of rejection and loss away, promising her that no one would ever be able to hurt her again.

There would be no going back now that she had given in. His heart (if he had it) broke for her, as he realized just how bleak her life would be now. If only he had realized it all sooner, maybe they could have stopped it. Now it was too late. There was nothing more he could do to bring her back. Not when she didn't want to come back.

"Swan…" he gasped, as her nails pierced deeper into the spongy flesh of his heart. "I'm sorry."

It wasn't enough. Not nearly enough. But it was all he could offer.

He could feel himself losing consciousness, feel the air being pulled from his lungs. He forced himself to look up at her, doing his best to let her know with a smile that he didn't hold her responsible for this; that he understood her, even at the end.

And then she looked back at him. He poured everything he wanted to say, everything he had every felt towards her with that look, and prayed that she could see it, even if it was only a memory. He hoped that someday, when she conquered the demon within her (and he had no doubt that she would destroy it eventually), she would know just how much he had loved her.

Then he closed his eyes, the pain in his heart finally too much to bear, as his strength gave out and his body sank to the floor. Therefore he didn't see her blink, as something shifted behind her eyes. He didn't see her looking down at the barely glowing object she held in her hand, as the light inside pulsed and faded. And he didn't see the smile falter on her lips, as a look of horror took its place.

"Killian?" She gasped, hardly daring to look away from the heart to the figure on the ground, willing away the truth for a few more blessed seconds. But she couldn't. She had to know, had to see just what had happened. "Oh, god. What am I doing?" She whispered, falling to her knees beside him. Gently she rolled him over so that she could lift his head and cradled it into her lap, as she checked for signs that he was still breathing.

He was, but barely. He stirred at her touch, and tried to smile. "Shh, love. All's fine now," He managed, the smile growing as he saw her eyes were now a bright shining green, even if they were blurry and wet. She began shaking her head furiously in protest, and he was overcome with the urge to reach up and comfort her. He stroked her cheek and wiping the wetness from beneath her eyes with his thumb. "Lost you for a moment, that's all. But you're back, now. You're here, that's all that matters."

This only made her cry even more, though it was a silent affair, where she nestled her face into his neck and clung to his shoulder. The only indication she was crying at all was the dampness seeping into his the collar of his shirt. At some point, she lifted her head and without warning, slid his heart gently back into place. It didn't hurt at all this time. For a second, he closed his eyes as the emotions came back in a rush. When he opened them, she was gazing at him with a look of deep remorse, and searching for words to say. He silenced her guilty conscious by pulling her towards him and kissing her with the same amount of passion and love that he had always had.

When they broke apart, her eyes were shining softly, and her fingers searched out his own and locking around them fiercely as if needing a physical link between them. However, as reality set in, not even his kisses could distract her from the weight of what she had done.

Frantically, she pushed him out of her lap and tried to stand. "I almost killed you. You need to get away from me."

He was faster and stood up before she could, grabbing on to her arm before she could run away. "No. Swan, I am not leaving you," he announced with as much authority as he could muster. The darkness had gotten to her once because of her walls, he wasn't about to let it happen again. He locked his gaze upon her and she stilled. "And don't even think about leaving me. We're stronger together."

"I don't want to hurt you," she said weakly, making a poor attempt at breaking free. Of course, he knew if she really wanted to, she could easily escape. But she didn't. She let him tear down her defenses, let him see between the cracks.

So he pulled her closer, and she came into his arms, as he held gently, cradling her body into his. Her hand came up to rest over his heart with the need to reassure herself that it was still there. "You didn't, my love. You _won't_." He pressed soft kisses into her hair and felt the last of the fight drain out of her.

"But I could have," she replied tensely, "God. I _wanted_ to. When I saw you and Lilly… my mind just…" She shook her head, clearing away the dark thoughts that wanted to reform. "I was convinced you had just been playing me. That you never loved me. I was certain you were just like all the others."

He grimaced, his lips sinking into her hair. "Never, my darling. I've only eyes for you."

"I know. I know," she pushed him back so that she could make sure she saw the truth on her face. "Killian. I trust you. I do. But this darkness, it's getting harder and harder to fight."

Her body shivered and she looked over at her friend who was lying unconscious on the ground. He let her go when she stepped away to check on her, and felt the tightness in his chest ease when Emma used her magic to heal any damage she had caused. She left Lilly to wake on her own time and returned to his side. He could see her worry about what would happen once the other girl woke up and knew he had to keep her from dwelling on it.

"I've something to show you, Swan," he announced, pulling her with him towards the toppled table, only dropping her hand long enough to fish out the small journal from the scattered heap of book and present it to her. "This is what I was looking at earlier. I believe it contains what we've been looking for- the Sorcerer's current location."

Her eyes grew wide as she flipped through the crackled pages. She found the page he directed her to, reading the same thing that had caused the sudden outburst that started it all. As she finished reading, he nuzzled in closer, leaning over her shoulder so that he could hold her tightly to him. Now that she was back, he was absolutely loathe to let her go.

His hand found hers while his hook wrapped around her waist. "We can find Merlin and destroy the Dark One once and for all. Together."

She laid her hand on top of his, and tilted her chin up so that their foreheads touched. He couldn't believe how right everything felt at that moment. She gave him a real smile, one that reached her eyes and made it seem like the sun had come out from behind the clouds. Only then did he know, without a trace of doubt, that his Emma was truly back.

"Together," she agreed.


End file.
